Documentation: nova: remove register abstraction task

The `register!` macro has been implemented and all nova-core code
converted to use it. Remove the corresponding task in todo.rst.

Reviewed-by: Eliot Courtney <ecourtney@nvidia.com>
Reviewed-by: Gary Guo <gary@garyguo.net>
Acked-by: Danilo Krummrich <dakr@kernel.org>
Link: https://patch.msgid.link/20260325-b4-nova-register-v4-10-bdf172f0f6ca@nvidia.com
Signed-off-by: Alexandre Courbot <acourbot@nvidia.com>
This commit is contained in:
Alexandre Courbot
2026-03-25 11:46:23 +09:00
parent 2278f97bb3
commit 1998e6be82

View File

@@ -51,82 +51,6 @@ There also have been considerations of ToPrimitive [2].
| Link: https://lore.kernel.org/all/cover.1750689857.git.y.j3ms.n@gmail.com/ [1]
| Link: https://rust-for-linux.zulipchat.com/#narrow/channel/288089-General/topic/Implement.20.60FromPrimitive.60.20trait.20.2B.20derive.20macro.20for.20nova-core/with/541971854 [2]
Generic register abstraction [REGA]
-----------------------------------
Work out how register constants and structures can be automatically generated
through generalized macros.
Example:
.. code-block:: rust
register!(BOOT0, 0x0, u32, pci::Bar<SIZE>, Fields [
MINOR_REVISION(3:0, RO),
MAJOR_REVISION(7:4, RO),
REVISION(7:0, RO), // Virtual register combining major and minor rev.
])
This could expand to something like:
.. code-block:: rust
const BOOT0_OFFSET: usize = 0x00000000;
const BOOT0_MINOR_REVISION_SHIFT: u8 = 0;
const BOOT0_MINOR_REVISION_MASK: u32 = 0x0000000f;
const BOOT0_MAJOR_REVISION_SHIFT: u8 = 4;
const BOOT0_MAJOR_REVISION_MASK: u32 = 0x000000f0;
const BOOT0_REVISION_SHIFT: u8 = BOOT0_MINOR_REVISION_SHIFT;
const BOOT0_REVISION_MASK: u32 = BOOT0_MINOR_REVISION_MASK | BOOT0_MAJOR_REVISION_MASK;
struct Boot0(u32);
impl Boot0 {
#[inline]
fn read(bar: &RevocableGuard<'_, pci::Bar<SIZE>>) -> Self {
Self(bar.readl(BOOT0_OFFSET))
}
#[inline]
fn minor_revision(&self) -> u32 {
(self.0 & BOOT0_MINOR_REVISION_MASK) >> BOOT0_MINOR_REVISION_SHIFT
}
#[inline]
fn major_revision(&self) -> u32 {
(self.0 & BOOT0_MAJOR_REVISION_MASK) >> BOOT0_MAJOR_REVISION_SHIFT
}
#[inline]
fn revision(&self) -> u32 {
(self.0 & BOOT0_REVISION_MASK) >> BOOT0_REVISION_SHIFT
}
}
Usage:
.. code-block:: rust
let bar = bar.try_access().ok_or(ENXIO)?;
let boot0 = Boot0::read(&bar);
pr_info!("Revision: {}\n", boot0.revision());
A work-in-progress implementation currently resides in
`drivers/gpu/nova-core/regs/macros.rs` and is used in nova-core. It would be
nice to improve it (possibly using proc macros) and move it to the `kernel`
crate so it can be used by other components as well.
Features desired before this happens:
* Make I/O optional I/O (for field values that are not registers),
* Support other sizes than `u32`,
* Allow visibility control for registers and individual fields,
* Use Rust slice syntax to express fields ranges.
| Complexity: Advanced
| Contact: Alexandre Courbot
Numerical operations [NUMM]
---------------------------